Hydraulic knee joint for artificial legs or leg braces



Aug. 15, 1950 T. H. coE, JR 2,519,226 HYDRAULICKNEE JOINT FOR ARTiFICIALLEGS OR LEG BRACES Filed Jan. 12, 1948 5 sheets-sheet i ATTORN 5Y5 Aug.15, 1950 T. H. COE, JR

HYDRAULIC KNEE JOINT FOR ARTIFICIAL LEGS OR LEG BRACES 5 Sheets-Sheet 2Filed Jan. 12, 1948 f5 INVENTOR.

ATTIDRN EYS Aug I 1- v CQE, JR 2,519,226

HYDRAULIC KNEE JOINT FOR ARTIFICIAL LEGS 0R LEG BRACES Filed Jan. 12,1948 v s Sheets-Sheet- 3 WW I M 2 720/7209 H Chm/g ATTCI RN EYE PatentedAug. 15, 1950 DRAUIEICZ KNEE J OINT; FOR ARTIFICIAL LEGSORLEG BRACESi.rhomastn.;ooe,iJr., Lakeville, Conn. 'A1)iflioation' January 12,19458, Serial No. B865 .sonms. (01.188493) Ehis. invention relatestan-hydraulic kneeijoint for-:artifieialslegs orlegabraces.

It is an object of the present inventionatmprovide aaflexible-support:for disabled :persons which Wilk give resistance "to movement of :theepartsa'of the support when the limbs or legs arefibeinglbent at rates ofspeed whichzmayberrregulatecl' *soaas to be difierentatdifferent-.portions;of:thedescent.

Other: objects 'of the .presentinvention are to providewa. jointrforaniartifieiali'leg or leg: brace which is of smooth act-ion; free oflocks andcatches; whereiniall-oi the mechanism is confined within ahousing and sealed in *a lubricant, which is free of gears, screws-andthe like, corn pact,1stur'dy; adapted to assume large loads, easy toassemble, simple in construction, inexpensive to manufacture, which willpermit "a free and,

natural step, and effioient in operation.

For a better understanding-ortho-invention,

reference may be had to the followingfdetailed description taken inconnection with theacoompanying drawing, in which Fig. 1 is a transverse:sectional view takenthrough the knee joint of the; present inventionand. generally on line l- I .ofFig; 21.

' FigJIZ is. a sectional .view, in elevation, itaken,

3 Fig.1'3. is. a sectional view of the. iointitaken on line ,3 3 ,otFig..1,

.Fig, .4 .isahside .elevational .view .of the joint showing the armportions extending therefrom andvwith portionsbrokenawamto show: thethrottle valve arrangement,

Fig. :5 is wan enlarged. sectional -.view taken, through the throttlevalve arrangement-and on' line 5-.-5- of Fig.4,

Fig. 6 is a fragmentary sectional :view taken-on line :6-E of 2,

"P is a-sectional viewer a :modifiedzformcof valvearrangementzas would.be'noted alongsaaline 1--i-'| of Figrfi, i

.Figs. 8; 9, c 10;. and T111i1IlISt1'8t6 respectively thestanding,.-sitting,.-steeping: or steppmg, andrhon' zontal'positions .ofthe iointzparts,

12 is a sectional view of themod'ified form oi theriinvention and takenon line ll-[Tot Fig. 7.

:z Fig. I3" is 'a detailillustratinga modification of the throttle valveWherein-asi-ngl'e plate'isiused,

-Fig514 is a view similar to that shown infFigure 13, with the valveplate shown in the closed posh tion.

1L5 is -a' similar detail illustrating :theiparts in the fulropen;position.

@Fig. a 16 ismsectional. plan similar. to; that: shown inlEigure 6,showing thevalve mounting -as.il1us-,

trated infiigures lsto L6.

Referring .now to the figures, represents 12a housing which .--may1 beof the shape shown :as

when the knee joint .of the present: invention; is:

to be used with leg braces or-:of-sphericalwshape when forming :a part:of an artifieialdimb. Ex-

tending from .the housing 1 is an arm l-B which will. eXtend-.-along thelower. leg. The housing has at: itsucenterwamprojectionore stud H to:which a second joint part or hub l 8 is fixed for adjust-' ment. Thehousing 1-5 willbe-adjustedzabout the part IS. The part l8.has.an-(arm l9 which-=will be..connected to the upper leg .or mayzxiorm the uppervleg part otanartificiallimb. The pro jeotion i! hasdiametricallyoppositesslotsl I, F igure. 2, for receiving projections 22:of the part 18 whereby "to retain-the parts against; lateral.displacementlfromone another when theprojections 22am angularlydisplacedfrom-the-slets Z I in the projections 11.

.Thehousing; l 5 is formed out portionsweldedtm getherattheirperipheries as-indicatectatllx At '50 thesection being. taken in aplane similar to that .of Figure 7.

one sideoi. the housing. ii are fixed v guidepontions 25 in which moveplates 26 and 21 separated from oneanother by...a partition 28. Theseplates'serve :as closuresfor-apertures 3| andSZ. The-platen has aportion .33, Figure-.2, which extends .overtheopening. .3 I when. theplate 26 .is. initslowered position.

iWithin .the... housing I 5 isan assemblage com-- prisingiacamffieandapiston 35. .The cam 34 will operate beneath the plate ZEto. lift thesame when the housing. [5. rotates with respect to the part [8. "The..cam .wilLacoordingly cause plate 26 tocharge the opening. .Sttothrottlethe liquid forced-toward the opening. 31 to a greater-extentas piston "35 travels .withi'nthe housing IS. The cami34 hasa.radially-inwardly; extending portion. 36 which enters arecess' of thepart. i3. The cam 34 is accordingly actuated byithe part.l8.

The. piston '35 is of arcuate shape 'andis adapted to. travellwithinthe'housingjfi. It has a; shoulder 31:.ad'apted to engage a stop.portion 38- of" the: housing to limit its movement in. one direction.Its movement. in the opposite .direction is limited by'an. adjustableset' sorewfifi. 'I'hepi'stoni35 has hinged flap .4! which is; moved toan :open position as thepiston is returned an arm 44 pivoted on thehOusing and adapted to be actuated by the part I 8, the arm having anextension 45 within a recess 46 in the part l8.

Assuming the body of the person is lowered from a position shown inFigure 8 to positions shown in Figure 9 and Figure 10, the resistance tocontrol the rate of descent is effected by raising of plate 26 over theopening 3| whereby to cause resistance to the flow of liquid through thehousing from piston 35 to the opposite side of opening 3| and when theflap 4| is closed. The cam 34 and the piston 35 are free to rotateclockwise when the parts are extended from either of the positions shownin Figures 9 and 10 to the position shown in Figure 8.

It will be apparent that the parts of this knee joint will varyaccordingly to the size of the person to make use of the same. One wayto adjust the joint to a difierent weight person is to use a plate 26with a difierent shape or size of portion 25'or to change the size ofthe aperture 3|. a threaded opening 41 in the housing which is normallyclosed by a screw plug 48. Likewise the shape of the cam 34-may bevaried. If it was found necessary to have rapid closing of the opening3! for the first few degrees it may be efiected by having the first partof the cam provided with a fastsurface.

The arrangement makes full use of friction to resist movement of theparts relative 'to one another. Gasket 49 is provided between the partsto prevent leakage of oil or other liquid within the housing and willprovide a frictional connection between the parts to resist theirmovement relative to one another.

Where the leg is extended as shown in Figure 11 as when the wearer is onthe ground and desires to rise, it is desirable that the lower leg bebrought easily to a vertical position. This action is the same asbending the knee except that the weight for operating the same lies onlyin the lower leg. This weight is only a small part of the weight of thebody of the wearer hence the speed of fiexure may be less. In order toprovide for this situation means has been provided to increasefthe speedof action under the circum stances.

Referring to Figure 1, it will be noted that the guides 25 for theplates 26 and 21 extend at a 'forty-five degree angle. Thus the plates25 and 21 are free to move under the pull of gravity if the joint isturned so that the plates may drop. As shown in Figure 5 the openings 3|and 32 are fully opened. As the lower leg moves toward the vertical theopening 3| is closed slowly by the cam 34 and by the plate 26 falling bygravity at a point somewhat below the forty-five degree angle. Theopening 32 will also be closed by the plate 21 falling by gravity. Theplate 21 and opening 32 are supplementary to plate 26 and opening 3|.The length of the plate 2'! may be used to control the size of theopening 32.

In Figure 7 and 12, there is shown a design where supplementary plate 21is delayed in its )closure movement upon the lower leg being brought tothe vertical position. The plate 21' is retained by the inclinedshoulder 5Ifbefore finally dropping over the lower 32'. shown in Figure6, is positioned between the plates 26' and 21', the plate 26' beingsimilar to the. plate 26, and adapted to close the opening 3lf as shownin Figure 12.

In the foregoing designs apertures of maxi- Access is had to the plates26 and 21 through part of opening A partition 28', similar to thepartition 28,

4 mum size have been provided as may be required for relatively lightweight users, wherein the throttle valve and the large aperturesrequired two sliding plates. It is also possible to use a single plateor valve element as illustrated in Figures 13 to 16 wherein a valve 52with an aperture 53 therethrough is slidably mounted between the guides54 and 55 withapertures 56 and-51 in the guide 54, and 58 and 59 in theguide 55. In this design a cam 69' similar to the cam 34 actuates thevalve 52 from the position shown in Figure 13, in which the leg isstraight and vertical, to the position shown in Figure 14, in which theknee is bent to the maximum, and all apertures are closed. In Figure 13the inner apertures 51 and 59 are open through the aperture 53, and inFigure 15, where the lower leg is horizontal and the valve has droppedby gravity all apertures are fully open. By this arrangement muchsmaller apertures may be provided, and it will be understood that one ora plurality of throttle valves or plates may be used as'may be desired.

The spring is compressed by the end of the lever 44 that is mounted withthe end 45 positioned in the recess 46, as shown in Figure 1, whereinthe spring 42 holds the part 18 in relation to the part l5 through thelever 44. Resistance is accordingly provided upon a slight movement ofone part relative to the other inasmuch as the recess 46 is short.Although the spring provides ease of movement between the parts it'isnot'essential to the operation of themade in the design and arrangementof the parts without departing from the spirit of the invention.

What is claimed is:

1. A hydraulic kneejoint for artificial legs and leg braces comprising ahousing having a center projection and an arm extending therefrom, asecond part locked with the center projection of the housing againstlateral displacement therefrom while permitting relative rotationbetween the parts, an arcuate piston operable through the housing toforce the liquid in one direction. a throttle valve arrangement forcontrolling the flow of liquid being delivered by the piston, and meansoperable between the housing and the part for controlling the throttlevalve arrangement, said means for operating the throttle valvecomprising a cam, said throttle valve including a plate and said camoperable beneath the plate to operate the same as the housing is angledrelative to the part.

2. A hydraulic knee joint for artificial legs and leg braces comprisinga, housing having a center projection and an arm extending therefrom, asecond part locked with the center projection of the housing againstlateral displacement therefrom while permitting relative rotationbetween the parts, an arcuate piston operable'through the housing toforce the liquid in one direction, a throttle valve arrangement forcontrolling the flow of liquid being delivered by the piston, and meansoperable between the housing and the part for controlling the throttlevalve arrangement, said throttle valve arrangement including guideportions extending from the housing, two plates for controllingrespectively two openings,

one opening supplementing the other opening.

for operating the throttle arrangement being operable from only one ofthe plates, said throttle valve arrangement extending at an angle offortyfive degrees whereby to permit free initial mcvement of the housingpart when brought from a horizontal position toward a vertical position.

3. A hydraulic knee joint for artificial legs and leg braces comprisinga housing havin a center projection and an arm extending therefrom, asecond part locked with the center projection of the housing againstlateral displacement therefrom while permitting relative rotationbetween the parts, an arcuate piston operable through the housing toforce the liquid in one direction, a throttle valve arrangement forcontrolling the flow of liquid being delivered by the piston, and meansoperable between the housing and the part for controllin the throttlevalve arrangement, said throttle valve arrangement including two valveplates one of which has an inclined shoulder, said housing having guideportions with a complementary inclined shoulder for delaying themovement of the valve plate until a predetermined angular position ofthe housing has been established and such that gravity action upon theplate will be delayed,

4. In a hydraulically controlled knee joint, the combination whichcomprises a substantially flat cylindrical housing having a centrallydisposed stud and having a leg mounting arm extended therefrom, a hubextended into said housing, pivotally mounted on said stud and alsohaving a leg mounting arm extended therefrom, said hub having a pistonextended therefrom and positioned in the housing, valve means in thehousing restricting flow of fluid actuated by the piston of the hub,means adjusting the position of the said valve means as the hub isrotated in the housing, and means releasing the fluid in the housing forthe return movement of the piston and. hub.

THOMAS H. COE, JR.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,587,207 Ackerman et a1. June 1,1926 1,675,760 Manzel July 3, 1928

